Irish lichens

Cresponea premnea

Order: Arthoniales       Family: Roccellaceae

Species: Cresponea premnea

Growth type crustose.
Photos: Killarney National Park, Co. Kerry, SW Ireland.
Identified by John Douglass

Thallus evanescent or thin and greyish-green. Apothecia with large black discs, +/- green-pruinose, margins persistent, +/- crenate. Pycnidia occasional, usually in groups or lines. Asci 8-spored, spores 5-septate, 18-25 x 5-7 Ám, usually curved and pointed.
Chemical reactions negative.

Found on well-lit, dry, rough bark of mature Oak, Yew and Beech in old woods and parks. Most Irish records are from the SE.

Sometimes found with Lecanographa lyncea

Cresponea premnea

Cresponea premnea

Cresponea premnea
Cresponea premnea November 2009

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